How to tell if audio and video are in sync?
 

I recently purchased a JVC SR-V10U, a TBC-1000, and an ATI TV Wonder 600 USB capture device. I plan to use VirtualDub to capture the video with a lossless codec. Once I am done capturing, is there any way to know that the capture went perfectly?

For example, no dropped frames and no inserted frames means the capture was perfect with perfect audio/video sync start to finish.

These are all old home movies. Some are over an hour. Once I am done capturing, I would like some "scientific" way to know that everything is archived perfectly so I can move on to the next. Otherwise, I find myself watching clips over and over staring at lip sync wondering if it off or correct.

I have never had equipment this nice before, so I hope this is the last time I have to attempt a perfect digital transfer. Other attempts have had issues.

Any suggestions?

Short of having clap boards (or similar percussive cues, such as a drum beat or door slam) in the video, let you ears and eyes be the judge, and recognize that lip sync can be adjusted in post production if necessary. Also, leading (early) audio is unnatural - the light reaches your eyes before the sound reaches your ears. Slightly trailing audio is natural - sound moves much slower than light. Expect the audio to lag by roughly a frame for every 38 feet the camera is from the sound source, potentially an outdoor and large venue concern.

Thanks for the response. I will just look at the result to determine if the sync is correct.

One other factor on lip sync. If the audio and video go through different (uncoordinated) paths they may have different latency. This can be found in mixed computer systems where separate sound and video capture/output cards are used. What looks/sounds right on the computer may be off when played in a DVD or BD player connected to a TV. You have to know what is going on in you system.